Carlton House. Pall Mall, London. Source: Ward, facing p. 31.
According to Humphry Ward's history of the London Athenaeum, "The immense development of club life which was to take place during the next ten years [after Waterloo (1814)] and which was entirely to transform Pall Mall, dates from the destruction of the Royal Palace, called Carlton House" [GPL].

Bibliography

Ward, Humphry. History of the Athenaeum, 1824-1925. London: Printed for the Club, 1926.